It was for next gen ATE at the time, Teradyne, etc. AP and SRS (SR1 has 39!) were opportunistic since obviously audio testing benefits from the same performance.
Which means the National LM series were one of the few designed for audio. Kind of tells you how big the market is for specialty audio monolithic circuitry.
So in the argument of IC vs discrete the issue should become LM based designs vs discrete.
Except of course that the AD797 may actually be better for many audio circuits then the LM equivalent.
Now my experience with the LM4562 is that it requires an input RF filter to work correctly in real circuits. Which is a bit different than just requiring the normal external parts.
As a side note building a reference design mic preamp circuit using an IC, the result was unacceptable. Low gain, irritating clipping and squeeging under some conditions. (Of course using almost exactly the same parts in a better topology yields a very useful preamp.)
I think National had a somewhat schizophrenic attitude about audio for a while, as there was considerable if sporadic activity and a sort of "personalization" afoot. I was at a degree of remove so I didn't know any of the players personally during that time, but from the advertising and also some of the material in Pease's columns, one could see a sort of strategy.
The reference designs for those LME parts have been spotty, for example the RIAA preamp. So it goes. But they are capable of excellent performance if you know what you are doing.
In some ways the development done before the TI acquisition has probably paid off adequately. Certainly TI dominates the so-called "digital" amplifier field. Someone I know who is doing some electronics work for Beats told me they don't leave much for him to do, as TI is taking no chances with that customer
For lower volumes you're probably pretty much on your own.
People compare apples to oranges and call one 'behind the times' Discrete, leaded, analog circuitry needs a certain amount SPACE just to remove the heat from the individual components. If you don't have enough SPACE you often have heat dissipation problems, circuit compromises, by reducing current, or thermal feedback, where you don't want it.
We try to avoid surface mount, except for servos, at this time.
When it comes to IC quality, I would say that the LME series is one of the most acceptable IC product range, and it is often used in newer audio designs, including my own.
We try to avoid surface mount, except for servos, at this time.
When it comes to IC quality, I would say that the LME series is one of the most acceptable IC product range, and it is often used in newer audio designs, including my own.
I think National had a somewhat schizophrenic attitude about audio for a while, as there was considerable if sporadic activity and a sort of "personalization" afoot. I was at a degree of remove so I didn't know any of the players personally during that time, but from the advertising and also some of the material in Pease's columns, one could see a sort of strategy.
The reference designs for those LME parts have been spotty, for example the RIAA preamp. So it goes. But they are capable of excellent performance if you know what you are doing.
In some ways the development done before the TI acquisition has probably paid off adequately. Certainly TI dominates the so-called "digital" amplifier field. Someone I know who is doing some electronics work for Beats told me they don't leave much for him to do, as TI is taking no chances with that customer
The joke always was the reference designs, even as the products improved the reference designs stayed the same.
As have many, and not meaning to suggest it's a new idea! But to have a specific focus of augmentation for given parts might be of interest.
One of the vexing details of some implementations concerns the guaranteed specifications of a given IC. This comes up for example when attempting the use of a part with the outputs taken from the positive and negative rail pins and those signals used ultimately to drive common-emitter or common-source external semiconductors. It's one of those "worked fine on the bench" approaches which can blow up in your face in production when the next batch of ICs has, say, a 50% higher quiescent current. I find this sort of thing difficult to argue when dealing with companies who believe building a hundred of something assures success in serious volumes.
Not too long ago I consulted on a three-way powered speaker in the form of a NASCAR model car. I was paid for the effort but the customer insisted on using their existing design, and when I pointed out that the manufacturer of the power IC explicitly said DON'T parallel these outputs, the customer assured me that they were still going to do so, and were confident, as they'd already done this in another product and it worked just fine. Astonishing arrogance. As the old investment disclaimer goes, past performance is no guarantee of future results.
The problem is Bcarso, it is difficult to make anything that is IC based, sound as good as an all discrete design, augmented or not, but we are working on it!
If many here can make an all IC based analog design that really sounds as good as the best discrete designs, go for it!. In fact, it might make you rich and as successful as the old Dyna company was many decades ago. Become a household name, just like Dyna!
If many here can make an all IC based analog design that really sounds as good as the best discrete designs, go for it!. In fact, it might make you rich and as successful as the old Dyna company was many decades ago. Become a household name, just like Dyna!
I think you'll find its already been done, but of course that depends how much of a sweeping statement you are making...
also, as far as heat, this has also mostly been solved with leadless parts, but it involves more involved and expensive PCB design techniques, PCB heatsinking is surprisingly good, much better than most of the discrete parts you use except for some of the large power devices (without extreme PCB measures)
I dont get this whole xenophobic thing, cant we all just get along and use the best currently available part for each job in the one design?
also, as far as heat, this has also mostly been solved with leadless parts, but it involves more involved and expensive PCB design techniques, PCB heatsinking is surprisingly good, much better than most of the discrete parts you use except for some of the large power devices (without extreme PCB measures)
I dont get this whole xenophobic thing, cant we all just get along and use the best currently available part for each job in the one design?
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And these statements are empty and useless, as there is no chance to make a direct comparison with CTC Blowtorch. On the other hand, it is possible to compare with Halo JC-2 quite easily and I know it is possible to make a competitive design (at least), even with ICs, when very high quality opamps and buffers are used.
If many here can make an all IC based analog design that really sounds as good ...
How about reading this and get another designers take on comparing a discrete & IC based pre-amp.
Ya, I say the same thing when someone says they can buy something cheaper & similar from Asia.
How about reading this and get another designers take on comparing a discrete & IC based pre-amp.
HTML:
http://www.a-and-t-labs.com/K12_Preamp/TheMetzPreamp2.pdfAlso this as well
K12 Preamp
I like these two parts the best,
K12 Preamp
I like these two parts the best,
Now this is what I call convincing and proof of concept, anything else, well it is words with little or no proof!!
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I sort of thought of it as letting a few folks off the leash to see what would happen. I assure you RIAA designs in 2000 did not generate sales volumne.
Did you ever hear the stories of John Belushi getting in the booth at fancy dance clubs and fooling the DJ into letting him put on some hardcore punk and then locking the DJ out.
What I admire about TI is few NS components that got dropped after the acq. Seems to be a good marriage, good for everyone. If you look back at PMI, for instance, lots of stuff was dropped after that action. So many more examples.
Yes, gotta like John Belushi & the crew.
Here's one for ya, I used John Candy's hand me down old hockey pants for a few years, then passed them onto my cousin after that, oh where did they go.We played road/ball hockey with JC as well, we put him in goal for obvious reasons There ya go again, another JC, John Curl your in good company, he was such a nice guy and you seem to be as well.
Yes, gotta like John Belushi & the crew.
Here's one for ya, I used John Candy's hand me down old hockey pants for a few years, then passed them onto my cousin after that, oh where did they go.We played road/ball hockey with JC as well, we put him in goal for obvious reasons
There ya go again, another JC, John Curl your in good company, he was such a nice guy and you seem to be as well.
The problem with audio is that it is a limited market. It is WELL KNOWN that many IC companies shy away from audio manufacturers. I can't necessarily blame them, after all it is difficult to 'understand' why a particular IC or even a particular IC package appears to sound different or worse than another. This tends to drive some engineers 'crazy' and the managers look at the bottom line and find that the volume just isn't there for quality audio products. It is not necessarily easy or obvious as to how to make a successful audio product. I have spent several years here,(mostly in vein) attempting to instill the 'extra quality' that makes a class A product. Most people think that it is the schematic that is all important, but that is only a part of a successful audio design. Layout is also very important, AND finally, someone with the 'ears' and self confidence to lead the way as to what parts sound good, what products sound bad, and to give the circuit designers feedback on this, so that we don't lose our way. I lost this last input with the death of Bob Crump, some years ago. He was the BACKBONE behind the CTC Blowtorch. He selected the switches, wiring, case type and size. My name, being better known in the industry, has been mostly used to identify the origin of the design, but without Bob, there would not have been any Blowtorch, its success in the World market, or even its sound quality. I, too, had to be moved from my earlier personal opinions as how to make a great preamplifier. I didn't know much about the Shalco switches, the silver wire, or a number of other things that make the product special, at least to our customers and ourselves. I will never make a preamp again that has as much promise to be exceptional.
News Flash! This guy, well; Just go to the link. A Scott 229b better than JC's Blowtorch at his home?
OOPS! edit; it was a Scott 299b
OOPS! edit; it was a Scott 299b
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Thanks Morinix, I wondered what Robin was doing lately. I tend to agree with him. Too much feedback in the solid state power amp, I would presume.
I first met Robin about 18 years ago, when he was a recording engineer in Berkeley. He did a lot of recordings of University orchestras at the time. He had an amazing collection of music as well. Once my friends bought a complete set of Grateful Dead CD's by mail order, and found them 'wanting'. We took them over to Robin, who listened to them with his headphones and said "They have been CEDARed." What an ear!
One thing that we shared was we each had a STAX Lambda Signature tube driven headphone system (still my reference) that was volume controlled by a dual Alps pot. We both found that the Alps was a major limitation in the system, and we both bypassed it at the time. Later, I found that the power line cord was another important factor, but that was later.
Robin has 'golden ears', better than most people I have ever met. After all these years, he remembered the very records that I chose to evaluate a system, including my own. What a musical memory!
If Robin says that the Scott edged out the Blowtorch-Parasound combination, then it is so, and as I already know, I don't know how to make anything 'perfect' yet.
I first met Robin about 18 years ago, when he was a recording engineer in Berkeley. He did a lot of recordings of University orchestras at the time. He had an amazing collection of music as well. Once my friends bought a complete set of Grateful Dead CD's by mail order, and found them 'wanting'. We took them over to Robin, who listened to them with his headphones and said "They have been CEDARed." What an ear!
One thing that we shared was we each had a STAX Lambda Signature tube driven headphone system (still my reference) that was volume controlled by a dual Alps pot. We both found that the Alps was a major limitation in the system, and we both bypassed it at the time. Later, I found that the power line cord was another important factor, but that was later.
Robin has 'golden ears', better than most people I have ever met. After all these years, he remembered the very records that I chose to evaluate a system, including my own. What a musical memory!
If Robin says that the Scott edged out the Blowtorch-Parasound combination, then it is so, and as I already know, I don't know how to make anything 'perfect' yet.
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You will find some of the parts unavailable, but maybe folks here could recommend some replacements. Anyone have subs for the Fairchild verticle MOSFETS, I'm not ready to part with my small stash?
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